The present invention relates to a connector for medical instruments which feeds electrical power from a power supply to the medical instrument with the use of a socket and plug.
An ultrasound treating instrument for performing a surgical operation with the use of ultrasound has been known. The ultrasound treating instrument includes a handpiece having a transducer and transmits an ultrasonic vibration which is generated in the transducer to a probe coupled to the handpiece and performs a treating operation with a forward end of the probe set in contact with a living body. A socket of an electric power feeding cable is connected to a plug of the handpiece and, through the cable, the electric power from the power supply is fed to the transducer in the handpiece.
When the handpiece is used, an electric power feeding cable for transmitting a drive current is previously connected to a respective individual handpiece. The probes, if differing in types, etc., act differently upon the living tissue. The probes are different in types and kinds and selectively used in accordance with the use to which they are put. The exchange of the probes to be attached to the associated handpieces takes a lot of time and labor since they are of a detachable screw-threaded type. Such an operation is not convenient during a surgical operation. The exchange of probes has to be done quickly in accordance with the situation under which the surgical operation proceeds. It is, therefore, convenient to make exchanges for handpiece units each with an initially prepared probe attached thereto instead of effecting the exchange for probes each time.
In the case where the exchange of initially prepared handpiece units is done instead of the exchange of probes each time, the associated handpiece has to be replaced by another handpiece together with a cable connected thereto.
In this case, since such handpieces have to be initially prepared with their own special cable connected thereto, the same number of cables are needed and the situations around the instruments are messy such as the entangling of cables. Further, it is necessary to select the needed cable and re-connect it to a power supply. It is cumbersome to re-connect the selected cable to the power supply.
It may be considered that a common cable is used for associated handpieces. In this case, those electric contacts of a plug section of the handpiece and those electric contacts of a socket section of the cable side are exposed to the exterior.
Normally, the respective electric contact sections are exposed to the exterior and they are inadvertently touched by the user. If this is the case, then the contact surface of the electric contact section becomes soiled and there is a risk that the electric conduction performance will be lowered.
In order to prevent a lowing in the electric conduction performance of the electric contacts, one contact is formed of a male type pin and the other contact is formed of a female type narrow hole. By doing so, these contacts are fitted together to create an electric connection. The treating instrument of U.S. Pat. No. 5,395,240 is shown as a pin/hole fitting type. For this reason, the cleanability of the contact section is not good.
The ultrasound treating instrument used for surgery is oftened soiled with humor and blood deposited on its contact section. If this soiled state is left as it is, the electric conduction performance of the electric contact is lowered. For this reason, it is necessary to deeply clean the contact section.
In the pin/hole connection type, however, if the connection section surface is soiled with blood, etc., the cleanability of it is not good. In order to enhance such cleanability, it is possible to use a structure with the connection section area opened. In such an open structure, the opening section of the connector becomes greater and the electric connection section is liable to be touched by human fingers. If the contacts are inadvertently touched by a finger, etc., and a shorting occurs between the contacts, then a discharge sometimes occurs due to a charge built up in the transducer inside the handpiece under a temperature variation involved. Further, due to the greater opening section of the connector, there is also a risk that the contact section will be soiled again with a foreign substance deposited thereon. If, for example, the open structure of the U.S. Pat. No. 5,807,392 is applied to an ultrasonic handpiece, the area between the pin contacts is liable to be touched by a finger and a discharge unavoidably occurs due to the presence of a charge involved.